SAN FRANCISCO (AP) - Andy Zhang walked over to the driving range as just another teenager wanting an autograph from his favorite players. Instead, he had the gallery at The Olympic Club asking for his signature.

All of 14 years old and preparing to start the ninth grade, Zhang is believed to be the youngest player in championship history. He was born in China and has lived in Florida since 2008, and about the only place he doesn’t show his age is on the course.

Heading to the driving range before his practice round Tuesday morning with Masters champion Bubba Watson and Aaron Baddeley was another story. Zhang was so giddy that his caddie, Chris Gold, had to calm him down.

“I was like, `Chris, can I go out on the range and ask for autographs?’” Zhang asked. “He said, `No. Today, you’re giving out the autographs.’”

After shedding some early nerves on the unleveled Lake Course, Zhang settled into a grove and even outdrove his more accomplished counterparts on occasion. By the end of the round, his smile _ behind those big braces, of course _ lit up the gallery and had everyone from Tiger Woods to Rory McIlroy wondering the same question.

Who is this kid?

“When I was 14, I was getting prepared to play in my club championship, not the U.S. Open,” said McIlroy, who set the tournament scoring record at 16-under 268 last year at Congressional. “So I’m not sure I could give him any words of wisdom.”

Zhang’s journey already has taken him around the planet.

He was born in Shandong, China, and started playing tournaments in the United States at age 10, when he won his division in the Junior World championship at Torrey Pines. Zhang took a trip with a friend to the David Leadbetter Golf Academy in the Orlando area shortly after and moved there four years ago without knowing a word of English.

Zhang taught himself the language.

“It was kind of funny because he would go to school and he would say hello and goodbye and that’s it,” Leadbetter instructor Andrew Park said by phone from Florida. “The following day he would say, `A, B, C.’ Eventually, we couldn’t keep him quiet his English was so good.”

The evolution of Zhang’s golf game also has been a natural progression.

Zhang lost in a playoff at a sectional qualifier in Florida and was the second alternate when the week began at Olympic Club. His father traveled back to China on business this week, but Zhang, his mother and caddie still showed.

Zhang wandered the grounds mostly as just a young fan and casual observer until Brandt Snedeker and Paul Casey withdrew with injuries late Monday evening while Zhang was on the putting range.

“I was right next to my mom and Chris. I was just giving them hugs and real excited,” he said.

Now Zhang is the talk of a locker room filled with players mostly twice his age _ or more _ who have been on the PGA Tour long before he was even born.

Tadd Fujikawa of Hawaii previously was the youngest in the modern era. He was 15 when he qualified for the 2006 U.S. Open at Winged Foot.

At first glance, Zhang might not look his age. He’s 6-feet tall and 174 pounds _ he even weighs himself every day. Then he smiles, shows off those thick braces and plays with an innocence nobody at Olympic Club can match.

Starting on the ninth tee just after 7 a.m., Zhang’s wayward drive landed deep into the trees and in the thick rough along the right side. He turned to Watson and asked politely, “Can I hit another one?”

“I’m like, `Dude, you’re in the U.S. Open, you can hit as many as you want in practice,” said Watson’s caddie, Ted Scott. “I just told him, `Look, just because you’re 14 doesn’t mean you can’t win.’ I say this: I don’t want to play him for money.”

Nobody is expecting anything from Zhang this week other than a couple rounds.

That hasn’t stopped Zhang from soaking in the experience. He picked up tips from Watson and Baddeley on the course, and Woods even sought him out in the locker room.

“I was like, `Wow, I just shook Tiger’s hand,’” Zhang said.

Even Woods, who won the Masters in 1997 before Zhang was born, heaped praise on the newest member in the clubhouse. He also defended any notion that Zhang might be too young to compete in “golf’s toughest test.”

“He qualified. He earned a spot. I tried it when I was 15, but he earned a spot,” Woods said. “That’s the great thing about this game, it’s not handed to you. You have to go out and put up the numbers and he did.”

Word of Zhang’s arrival spread throughout Olympic and fans of all ages gathered to watch the youngster in packs.

He sprinkled in autographs while walking the course and even posed for a picture or two. Alex Gotz of nearby Tiburon had the best view all day as the standard bearer.

The 15-year-old walked with the group all day _ Watson only played the back 10 holes in the morning before jetting off _ and was amazed at Zhang’s talent and composure.

“I’m behind the curve I guess,” Gotz joked.

Then, he added: “Well, it is the U.S. Open. I guess anybody really can play here.”